IN-VITRO COMPARISON OF SHEAR BOND STRENGTH AND DEBONDING CHARACTERISTICS OF TWO ADHESIVE SYSTEMS

Abstract

Introduction: With the introduction of new orthodontic materials, it is imperative to evaluate them, both clinically and in-vitro, before recommended for daily clinical use. Shear bond testing, in-vitro, serves as a quick and effective way of testing bond strength of the orthodontic adhesives. Results enable the clinician to choose a superior and more suitable material.

Objectives: To compare the shear bond strength and debonding characteristics of two orthodontic adhesives.

Study Design: Quasi-Experimental

Sampling Technique: Non Probability/ Convenience

Setting: The study was conducted at Armed Forces Institute of Dentistry, Rawalpindi.

Materials and Methods: 60, freshly extracted bovine incisors were divided into two groups, A and B, of thirty each.  Stainless steel, metal, Roth 0.022†slot brackets were bonded to the teeth. Teeth in Group A were bonded using Transbond Plus Self Etchant Primer system, those in group B were bonded using Transbond XT system. After storage in normal saline at room temperature for 24 hours, the samples were subjected to shear bond testing. The Adhesive Remnant Index (ARI) was calculated for each bracket under magnification. The data was analyzed using the student’s t-test, with the level of significance set at p≤ 0.05.

Results: Mean shear bond strength for Group A was, 5.97 ±1.23MPa while for Group B was 6.56±1.23MPa. Group B showed higher Adhesive Remnant Index scores than did Group A samples. The results were statistically significant, p<0.05.

Conclusion: The shear bond strength of the Self etchant primer system was significantly less than the conventional bonding agent; however, it was still within clinically acceptable limits.